Kabushiki Kaisha Bridgestone

Bridgestone Corporation

Hiroshi Morinaga

Yasumichi Wakao

Yasushi Hanatsuka

Hidetoshi Yokota

Shinya Tsuchida

Go Nagaya

Kazuma Nakazawa

Akira Kobayakawa

Koji Otani

Tomonori Ohiro

The invention provides an apparatus, program, and method for controlling the automatic spraying of an antifreezing agent that can reduce the cost of the antifreezing agent and the impact of salt damages caused by the antifreezing agent. This is accomplished by reducing the amount of antifreezing agent to be sprayed automatically according to road surface condition and reducing the amount of the antifreezing agent left unused on completion of the spray operation by grasping in advance the total spray amount of the antifreezing agent. Thus, the antifreezing agent automatic spray control apparatus comprises a spray section setting unit for setting a spray section, a road surface condition data acquiring unit for acquiring road surface condition data, a spay condition data acquiring unit for acquiring spray condition data, a spray condition determining unit for determining the spay conditions for each of unit sections, a total spray amount advance calculating unit for calculating in advance the total spray amount of antifreezing agent to be sprayed for the spray section, a current position data acquiring unit for acquiring current position data, a unit section identifying unit for identifying a unit section corresponding to the current position, and a spray condition outputting unit for outputting the spray conditions for each of the unit sections to an antifreezing agent spraying unit.

Apparatus, program, and method for controlling automatic spray of antifreezing agent

A method capable of estimating a snowy road surface condition during vehicular travel in finer classification. In this method, tire vibrations in the circumferential direction, road surface temperature (T), and tire-generated sound are detected by an acceleration sensor, a road surface thermometer, and a microphone, respectively. Then band values P, Pand Pfor a pre-leading-edge region (R), band values P, Pand Pfor a leading-edge region (R), band values P, Pand Pfor a pre-trailing-edge region (R), band values Pand Pfor a trailing-edge region (R), and band values P, Pand Pfor a post-trailing-edge region (R) are calculated from the tire vibration data. A sound pressure level ratio (Q)=(P/P), which is the ratio of a band power value (P) of a low frequency band to a band power value (P) of a high frequency band, is calculated from data on the tire-generated sound. And a road surface condition is estimated, using the band values (P), road surface temperature data (T), sound pressure level ratio (Q), and wheel speed data.

Method for estimating road surface condition

The vibration of a tireof a running vehicle in the circumferential direction or the width direction is detected by a road surface condition estimating tire, provided with an acceleration sensorand a signal processing unit. Data of a detected vibration waveform are divided into data of three domains, namely, a pre-leading domain, a contact patch domain, and a post-trailing domain, and then the vibration levels in the pre-leading domain and the contact patch domain, respectively, are extracted. At the same time, a vibration component in a low-frequency band and a vibration component in a high-frequency band are extracted respectively from the vibration levels in the respective domains, and respective vibration level ratios R, which are each a ratio thereof, are calculated. Then, on the vehicle body side, the condition of a road surface on which the vehicle is running is estimated, based on the calculated vibration level ratio R and a mapM, stored in a storage means, showing a relationship between the vibration level ratio R of tire vibration and road surface conditions. Thus a road surface condition can be estimated with accuracy even when there are changes in temperature or vehicle speed.

Road surface condition estimating method, road surface condition estimating tire, road surface condition estimating apparatus, and vehicle control apparatus

The degree of tire wear is estimated with constancy and accuracy even when the road surface becomes rough during a vehicular run. The deformation speeds Vand Vof the tread of the tire are obtained respectively by calculating the levels of peaks Pand Pat contact edges appearing in the differentiated waveform of radial acceleration detected by an acceleration sensorinstalled on the inner surface in the inner liner region of the tire. An average standardized deformation velocity Vis calculated as the average of the absolute values of leading-edge-side standardized deformation speed Vand trailing-edge-side standardized deformation speed V, which are obtained by standardizing the Vand Vusing the rotation time Tof the tire. At the same time, an extra-contact-patch vibration level v of the tread is detected from the radial acceleration having passed through a bandpass filter. And a degree M of tire wear is estimated, using the average standardized deformation speed V, the extra-contact-patch vibration level v, and a mapM.

Method for estimating tire wear and apparatus for estimating tire wear

The degree of wear of a tire is estimated with constant accuracy. An acceleration sensor () is installed on the inner surface in the inner liner region of a tire to detect the acceleration of the tread in the radial direction of the tire. The peak level on the leading edge side or the trailing edge side of the tread appearing in the differentiated waveform of the detected acceleration is calculated and used as an index V of deformation speed of the tread. The degree of wear of the tire is estimated on the basis of the calculated index V of deformation speed and an M-V map (B) showing a predetermined relationship between the degree M of tire wear and the index V of deformation speed.

Method for estimating the wear of a tire

In order to accurately and stably estimate the conditions of a running tire, a vehicle is equipped with a sensor-incorporating tire having, at an equal distance from the center in the axial direction of the tire, pressure sensors (A,B) buried in a tread rubber positioned on the outer side in the radial direction of the tire belt layer of a tire tread portion and on the inner sides in the radial direction of tread blocks, the contact length Lof the car body side and the contact length Lof the opposite side of the center in the axial direction of the tire are detected by using the duration times of pressure values from the pressure sensors (A,B) and a wheel speed from a wheel speed sensor (), and the ratio R=L/Lof the contact length Lto the contact length Lis computed to estimate lateral force generated by the tire, or the average contact length Lwhich is the average value of the contact lengths Land Lis computed to determine a load applied to the tire.

Sensor-incorporated tire and tire condition estimating method

The dynamic state amount of a tire when a load is applied to the tire while running can be estimated accurately and stably by installing tire deformation amount measuring meansA andB at axisymmetrical positions which are equally distant in the axial direction from the center in the axial direction of the tire on the cross-section in the radial direction of the tire on the inner side of the belt portion of a tire tread in the radial direction, such as at the inner surface of the tread, between an inner liner and a ply, between plies or between a ply and a belt to measure the waveforms of deformation of the tire, detecting the contact time which is the time difference between contact edges from the waveforms of deformation, calculating contact length indices kand kfrom the contact time and the wheel speed detected by a wheel speed sensor, calculating the average value k of the above indices kand k, and obtaining a load applied to the tire by using the calculated average value k of the indices of contact length and a mapM showing the relationship between the average value of the indices of contact length and load pre-stored in memory means

Estimation method and apparatus of tire dynamic state amount and tire with sensors

The frequency of an information signal indicative of a-vibration of a wheel detected by an acceleration sensor mounted to a wheel; or a change in the pressure of a gas in a tire detected by a pressure sensor installed in the tire, is analyzed. The band value of the obtained vibration spectrum or pressure change spectrum is detected, and a vibration level or pressure change level at the detected frequency band is compared with: a vibration level table showing the relationship between road friction coefficient &#x3bc; and vibration level; or a pressure change level table showing the relationship between road friction coefficient &#x3bc; and pressure change level, to estimate a road friction coefficient &#x3bc;. Therefore, it is possible to estimate the value of road friction coefficient &#x3bc; accurately and improve the safety of a car.

Method and apparatus for estimating road surface state and tire running state, ABS and vehicle control using the same

A purpose of the present invention is to provide a rim wheel and a tire rim assembly which are capable of effectively reducing cavity resonance of a tire, and accordingly, enhancing quietness and riding comfort. A plurality of cap membersis arranged on an outer circumferential surface of a rimin a circumferential direction thereof, diaphragms are disposed inwardly of each cap member, and a plurality of sub-air chambersis formed between the rimand the cap membersin a rim circumferential direction. The tire main air chamberis connected to the sub-air chambersthrough communicating holesformed on the cap members. The sub-air chambersand the communicating holesconstitute a Helmholtz resonance noise absorber that can absorb vibration with specified frequencies. Further, since the sub-air chamberis not formed in a continuous annular shape in a tire circumferential direction, occurrence of cavity resonance can be suppressed and a substantial reduction in noise can be secured.

Rim wheel, and tire-rim assembly

The output level of vibration of a portion below the spring of a vehicle detected by a sensor, and its frequency is converted to obtain the frequency spectrum of the vibration level. Next, an operation is carried out on at least two vibration levels, at different frequency bands. The computed value is compared with a master curve showing the frequency spectrum of vibration level stored in vibration level storage to estimate the condition of a road surface so as to estimate the running state of the vehicle. Further, the running state of each tire including air pressure is detected from the vibration level of the portion below the spring to estimate the running state of the vehicle. Thereby, a multi-function sensing system is constructed for estimating the condition of a road surface or the running state of the tire with one sensor.

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Tokyo, Japan

Hiroshi Morinaga